The present invention relates to a method of forming novel Si--O containing coatings. The method comprises treating Si--O containing ceramic coatings derived from hydrogen silsesquioxane resin with hydrogen gas. The resultant coatings have desirable properties.
The use of silica-containing ceramic coatings derived from hydrogen silsesquioxane resin on electronic devices is known in the art. For instance, Haluska et al. in U.S. Pat. No. 4,756,977 describe processes for forming coatings on electronic devices which comprise diluting hydrogen silsesquioxane in solvents, applying the solutions to substrates, evaporating the solvents and heating the coated substrates to a temperature of about 150.degree. to about 1000.degree. C. in air. This patent, however, does not describe annealing the coatings with hydrogen gas.
The conversion of hydrogen silsesquioxane resin to a Si--O containing ceramic in other environments is also known in the art. For instance, European Patent Application No. 90311008.8 teaches the conversion of hydrogen silsesquioxane resin to a Si--O containing ceramic by heating a substrate coated with the resin in an inert gas atmosphere. This patent too, however, does not describe annealing the coatings with hydrogen gas.
The present inventor has now discovered that when Si--O containing coatings derived from hydrogen silsesquioxane resin are treated with hydrogen gas, the properties of the coating are improved.